1. Field of Invention
This invention relates to diving, swimming, or other face masks, specifically to the wiping of fog from the inner surface of the viewing face plate(s).
Diving masks or swimming goggles are prone to the formation of fog on the interior surface of the viewing face plate(s). This occurs because of the moisture and temperature difference between the two sides of the glass. This fog (or more technically, condensation) is a significant viewing obstruction.
There exist diving masks equipped with so-called antifog lenses. However, these lenses appear only in the highest levels of professional equipment, and are not used in amateur-level equipment. As a result, most diving masks continue to fog-up.
There also exist methods and structures for defogging eye wear. Such methods and devices employ electrically generated heat or ventilation channels which are difficult to accommodate under water. For these reasons defogging methods and devices have not found their way into diving masks.
Currently, there exist only two methods for addressing the fog problem in diving masks: rinsing the fog via partial removal of the mask under water, and application of defogging agents to the interior side of the glass prior to the placement of the mask on the face. The first method has numerous disadvantages, including the call for considerable training, and loss of valuable air. The second method relies on the persistence of the defogging agent to remain on the glass, the impossibility of re-application under water, and health concerns over the use of chemicals.
A solution to all of these disadvantages is to provide a means of mechanically removing or wiping the fog without removing the mask, which is the function of our invention. In addition to several other components, our invention involves a pair of magnetically coupled units sandwiching the viewing face plate of the mask. Both units have at least one surface that is porous and nonabrassive, and one or both units are magnet, and if one is not a magnet, then it is magnetizable. In this way, the two units can be placed on either side of the glass--one on the inside (called the slave unit) and the other on the outside (called the master unit)--while magnetically coupled to one another. Then, any time the master unit is moved across the outside surface of the glass the slave unit follows in unison, thereby wiping fog off the inside surface of the glass. Furthermore, our invention involves a resting unit that provides a resting place for the slave unit while it is not being used.
2. Description of the Prior Art
U.S. Pat. Nos. 3,600,737, 3,731,337, 3,759,621, 3,839,085, 3,922,747, 3,983,591, 4,921,614, 4,977,637, and 5,515,570, are believed good examples of the state-of-the-art. All of these patents involve the magnetic coupling of two units disposed on the opposite sides of a surface.
Improvements on these patents have been made by addressing the status of the slave unit when it is not being used. U.S. Pat. No. 3,751,750 describes a "locator" for temporarily attaching to the window opposite the slave unit. U.S. Pat. No. 4,144,091 describes a "container" affixed to the slave-side of the window pane used for storing the slave unit. U.S. Pat. No. 5,900,374 describes a "holder" consisting of a pair of elastic wings which are adjusted at such an angle to hold the slave unit in place when it is not being used.
Such a "locator" requires access to both sides of the glass during operation; however, there is no access to the inside of a diving mask during operation and so, such a locator cannot be used. Since a diver wearing a mask moves his/her head from side to side and from up to down, a "container" cannot contain the slave unit, and if the slave unit exits the container, it not only can hit the divers face, but also leave the magnetic field region of the master unit and be lost in the mask. A "holder" has three disadvantages: 1) adjusting the angle and the elasticity of the wings is difficult, at best; 2) it can fail when there are wide variations in temperature and humidity in the medium wherein the device operates, as in under sea water, and 3) it has many moving parts, and so, can fail to capture the slave unit altogether.
Therefore, when the slave unit is not being used for wiping, it is crucial to assure that the slave unit is 1) removably affixed to the inside of the mask, so that when the master unit is brought to the outside of the glass the two can couple together, 2) rests sufficiently close to the inside surface of the glass, again, to allow magnetic coupling with the master unit when the latter is brought to the outside of the glass, and 3) kept out of the line of sight, and in a fail-safe fashion.
The primary difference between the current invention and all the prior art inventions is in having a resting unit, magnetically coupled to the slave unit when it is not being used. As such, it is simple to construct, without sensitive adjustments, insensitive to environmental conditions, and keeps the slave unit close to the viewing face plate and out of the line of sight. Without such a resting unit, none of the prior arts can be adapted to perform the function of wiping fog from the inside surface of the viewing face plate in a diving mask. Further, the resting unit can be simply trimmed and shaped to fit any mask, because it is a flexible, springy, wire (generally known as "piano wire" among hobbyists and model airplane builders).
It is important to emphasize that currently there does not exist any device for that purpose. What does exist is methods for rinsing the fog, means for avoiding fog, and methods that can be adapted to wiping fog. Our invention has numerous advantages over these alternatives, including the following: It 1) can be used continually and whenever desired, 2) is undepletable, 3) is chemical-free, 4) has no components that may wear out, and 4) has no sensitive moving parts, and so, cannot fail. Furthermore, if desired, defogging agents can be naturally incorporated into our invention by soaking the porous nonabrassive material on the slave unit in a defogging liquid, thereby allowing the defogging agent to be automatically applied and re-applied to the inside surface of the viewing face plate each time the device is used for wiping the fog.